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971.
Lee SA Lee KM Park WY Kim B Nam J Yoo KY Noh DY Ahn SH Hirvonen A Kang D 《Experimental & molecular medicine》2005,37(2):86-90
To evaluate the relationship of genetic polymorphisms of ERCC2 and ERCC4 genes, both involved in nucleotide excision repair (NER), and the risk of breast cancer, a hospital-based case-control study was conducted in Korea. Histologically confirmed breast cancer cases (n = 574) and controls (n = 502) with no present or previous history of cancer were recruited from three teaching hospitals in Seoul during 1995-2001. Information on selected characteristics was collected by interviewed questionnaire. ERCC2 Asp(312)Asn (G>A) was genotyped by single-base extension assay and ERCC4 Ser(835)Ser (T>C) by dynamic allele-specific hybridization system. Although no significant association was observed between the genetic polymorphisms and the risk of breast cancer, women with both ERCC2 A allele- and ERCC4 C allele-containing genotypes showed a 2.6-fold risk (95% CI: 1.02-6.48) of breast cancer compared to women concurrently carrying the ERCC2 GG and ERCC4 TT genotypes. The breast cancer risk increased as the number of "at risk" genotypes increased with a borderline significance (P for trend = 0.07). Interactive effect was also observed between ERCC4 genotype and body mass idnex (BMI) for the breast cancer risk; the ERCC4 C allele containing genotypes posed a 1.7-fold (95% CI: 0.96-2.93) breast cancer risk in obese women (BMI>25 kg/m(2)) with a borderline significance. Our finding suggests that the combined effect of ERCC2 Asp(312)Asn and ERCC4 Ser(835)Ser genotypes might be associated with breast cancer risk in Korean women. 相似文献
972.
Cheng F Kelly SM Young NA Clark S Francesconi MG Lefebvre F Bradley JS 《Chemical communications (Cambridge, England)》2005,(45):5662-5664
We report a general method for the preparation of transition-metal silicon nitride nanocomposites; for example, mesoporous Pd-Si3N4 nanocomposite materials with high surface area were prepared by pyrolysis of a silicon palladium imide-chloride complex which was synthesized by reaction of silicon diimide gel with palladium chloride. These porous nanocomposites catalyse organic reactions. 相似文献
973.
974.
Amitay Noach Lavi Abrahim Young Frederick 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1961,12(2):89-99
Zusammenfassung Für den eingeschwungenen Zustand dertapered-plane transmission line wird eine neue Lösungsmethode beschrieben und gezeigt, dass die Impedanztransformation direkt vom Verhältnis der Abstände zwischen Anfang und Ende der leitenden Ebenen bestimmt wird. Die Phasendifferenz der Spannungen zwischen den Leitungsenden ist dem Öffnungswinkel der beiden Ebenen proportional. Kriterien für den Entwurf solcher Leitungen lassen sich angeben.
This work was submitted byNoach Amitay in partial fulfillment of the Degree Doctor of Philosophy. 相似文献
This work was submitted byNoach Amitay in partial fulfillment of the Degree Doctor of Philosophy. 相似文献
975.
Given a poset we introduce the notion of Q-upper algebras and study the (positive) implicativity, commutativity and quasi-commutativity in Q-upper algebras. 相似文献
976.
The production of atomic iodine in the ground (2Pfrsol|3/2) and electronically excited (2P) states following laser-induced photodissociation of I2 the region 425–498 nm was monitored directly by resonance spectroscopy. The branching ratio for iodine atom formation. R = [I(2P)]/[I(2P)], is above 0.5 in the region 495–498 nm in agreement with the recent observation of laser action on the atomic transition at 1315 nm following photolysis of I2 using a dye laser. The present experiments permitted deconvolution of the I2 continuous absorption spectrum below 498 into contributions from the B3 Πo,u → X 1Σg+ and 1Πtu → X1σg? transitions. 相似文献
977.
978.
979.
Paul Barraclough Sevin Bilgic J. Brian Pedley Antony J. Rogers Douglas W. Young 《Tetrahedron》1979,35(1):99-103
The 1H-NMR, 13C-NMR and photoelectron spectra of a variety of 2-heterobicyclo[3.2.1]octa-3,6-dienes 6 give evidence of conjugative and homoeonjugative effects in these compounds, but there is no suggestion from the data of any special contribution from the (4n+2)π neutral bishomoaromatic system. Reaction of the dienes6 with TCNE invariably yielded the product of [2+2] addition in cases where a fully characterisable product was obtained. 相似文献
980.